Method of manufacturing a geodetic component and integrated optical device comprising said component

Abstract

A method of manufacturing a geodetic-optical component is described in which non-spherical rotationally symmetrical recesses are formed in a surface of a substrate, and the surface with the recesses are covered with a planar waveguide. This technique forms the recesses in a laminated substrate having a number of layers of varying etching rates, and then etching these layers to form cup-shaped recesses.

What is claimed is: 
     
       1. A method of manufacturing a geodetic-optical component having non-spherical rotationally symmetrical recesses comprising the steps of applying a number of substantially equally thick layers onto a surface of a support body, said support body and said layers forming a laminated substrate,   forming a masking layer on said laminated substrate with openings at selected recess locations,   etching said laminated substrate through said openings with an etchant having an etching rate varying with the number of said layers to form said non-spherical rotationally symmetrical recesses, and   providing a planar waveguide on said recesses after removing said masking layer.   
     
     
       2. A method according to claim 1, wherein said etching rate decreases with increasing number of said layers. 
     
     
       3. A method according to claim 1 or claim 2, wherein said layers are formed by using a non-isothermal plasma CVD technique. 
     
     
       4. A method according to claim 1 or claim 2, wherein said etchant consists of phosphoric acid. 
     
     
       5. A method according to claim 1 or claim 2, wherein said recesses are cup-shaped. 
     
     
       6. An optical device comprising a laminated structure of a number of substantially equally thick layers on a surface of a support body, at least one non-spherical rotationally symmetrical recess in said laminated structure, and a plasma waveguide on said recess. 
     
     
       7. An optical device according to claim 6, wherein said recess is cup-shaped. 
     
     
       8. An optical device according to claim 6 or claim 11, wherein said planar waveguide is a 50 μm thick layer of a material having a higher refractive index than said laminated structure.